Hi there,
If you have a file server, presumably you have a way for people to download files from it externally, and that "way" must have an address for people to access through? Something like "ftp://myfiloserver.mydomain.com/" or something? So why not just put in a link tag (an "a" tag) that links directly to the FTP server file. For example:
<a href="ftp://myfiloserver.mydomain.com/A Folder/My EXE file.exe">My EXE File</a>
This should work, I've seen it done on other sites :)
Hope this helps,
Ed